X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=361820bd0649854640e0252eeab4a47fb961afe3;hp=0b76cc3d7321d768fe16f590f72644b38388f014;hb=7d0f82bd4b7044a5151835e25e830fd28dfaaebd;hpb=c04c84c98055c6b9e9e7890d3992648a3b715a1a diff --git a/src/protocol.c b/src/protocol.c index 0b76cc3d..361820bd 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -17,7 +17,7 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: protocol.c,v 1.28.4.30 2000/09/14 11:54:51 guus Exp $ + $Id: protocol.c,v 1.28.4.59 2000/11/07 22:02:14 guus Exp $ */ #include "config.h" @@ -36,48 +36,103 @@ #include +#include +#include +#include + #include "conf.h" -#include "encr.h" #include "net.h" #include "netutl.h" #include "protocol.h" +#include "meta.h" +#include "connlist.h" #include "system.h" -/* Generic outgoing request routine - takes care of logging and error detection as well */ +int check_id(char *id) +{ + int i; + + for (i = 0; i < strlen(id); i++) + if(!isalnum(id[i]) && id[i] != '_') + return -1; + + return 0; +} + +/* Generic request routines - takes care of logging and error detection as well */ -int send_request(conn_list_t *cl, const char *format, int request, /*args*/ ...) +int send_request(conn_list_t *cl, const char *format, ...) { va_list args; - char *buffer = NULL; + char buffer[MAXBUFSIZE]; + int len, request; + cp - if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), requestname[request], cl->id, cl->hostname); + /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic, + and there is a limit on the input buffer anyway */ va_start(args, format); - len = vasprintf(&buffer, format, args); + len = vsnprintf(buffer, MAXBUFSIZE, format, args); + request = va_arg(args, int); va_end(args); - if(len < 0 || !buffer) + if(len < 0 || len > MAXBUFSIZE-1) { - syslog(LOG_ERR, _("Error during vasprintf(): %m")); + syslog(LOG_ERR, _("Output buffer overflow while sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); return -1; } - if(debug_lvl >= DEBUG_META) - syslog(LOG_DEBUG, _("Sending meta data to %s (%s): %s"), cl->id, cl->hostname, buffer); + len++; + + if(debug_lvl >= DEBUG_PROTOCOL) + syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); + +cp + return send_meta(cl, buffer, len); +} - if(cl->status.encrypted) +int receive_request(conn_list_t *cl) +{ + int request; +cp + if(sscanf(cl->buffer, "%d", &request) == 1) { - /* FIXME: Do encryption */ - } + if((request < 0) || (request > 255) || (request_handlers[request] == NULL)) + { + syslog(LOG_ERR, _("Unknown request from %s (%s)"), + cl->name, cl->hostname); + return -1; + } + else + { + if(debug_lvl >= DEBUG_PROTOCOL) + syslog(LOG_DEBUG, _("Got %s from %s (%s)"), + request_name[request], cl->name, cl->hostname); + } + + if((cl->allow_request != ALL) && (cl->allow_request != request)) + { + syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), cl->name, cl->hostname); + return -1; + } - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(request_handlers[request](cl)) + /* Something went wrong. Probably scriptkiddies. Terminate. */ + { + syslog(LOG_ERR, _("Error while processing %s from %s (%s)"), + request_name[request], cl->name, cl->hostname); + return -1; + } + } + else { - syslog(LOG_ERR, _("Sending meta data failed: %m")); + syslog(LOG_ERR, _("Bogus data received from %s (%s)"), + cl->name, cl->hostname); return -1; } -cp +cp + return 0; } /* Connection protocol: @@ -85,93 +140,102 @@ cp Client Server send_id(u) send_challenge(R) - send_chal_reply(BH) - send_id(B) - send_challenge(BR) - send_chal_reply(BH) - send_ack(B) - send_ack(B) + send_chal_reply(H) + send_id(u) + send_challenge(R) + send_chal_reply(H) + --------------------------------------- + send_metakey(R) + send_metakey(R) + --------------------------------------- + send_ack(u) + send_ack(u) + --------------------------------------- + Other requests(E)... (u) Unencrypted, (R) RSA, (H) SHA1, - (B) Blowfish. + (E) Encrypted with symmetric cipher. - Part of the challenge is directly used to set the blowfish key and the initial vector. - (Twee vliegen in één klap!) -*/ + Part of the challenge is directly used to set the symmetric cipher key and the initial vector. + Since a man-in-the-middle cannot decrypt the RSA challenges, this means that he cannot get or + forge the key for the symmetric cipher. +*/ int send_id(conn_list_t *cl) { cp - return send_request(cl, "%d %s %d %s", ID, myself->id, myself->version, opt2str(myself->options)); + cl->allow_request = CHALLENGE; +cp + return send_request(cl, "%d %s %d %lx %hd", ID, myself->name, myself->protocol_version, myself->options, myself->port); } int id_h(conn_list_t *cl) { conn_list_t *old; - char *options; + config_t const *cfg; cp - if(sscanf(cl->buffer, "%*d %as %d %as", &cl->id, &cl->version, &options) != 3) + if(sscanf(cl->buffer, "%*d %as %d %lx %hd", &cl->name, &cl->protocol_version, &cl->options, &cl->port) != 4) { syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname); return -1; } - + /* Check if version matches */ - - if(cl->version != myself->version) - { - syslog(LOG_ERR, _("Peer %s uses incompatible version %d"), cl->hostname, cl->min_version, cl->max_version); - return -1; - } - /* Check if option string is valid */ - - if((cl->options = str2opt(options)) == -1) + if(cl->protocol_version != myself->protocol_version) { - syslog(LOG_ERR, _("Peer %s uses invalid option string"), cl->hostname); + syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"), + cl->name, cl->hostname, cl->protocol_version); return -1; } - + /* Check if identity is a valid name */ - - if(!check_id(cl->id)) + + if(check_id(cl->name)) { syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname); return -1; } - + /* Load information about peer */ - - if(!read_id(cl)) +cp + if(read_host_config(cl)) { - syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->id); + syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name); return -1; } - /* First check if the host we connected to is already in our connection list. If so, we are probably making a loop, which is not desirable. */ - +cp if(cl->status.outgoing) { - if((old=lookup_id(cl->id))) + if((old = lookup_id(cl->name))) { - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->id, cl->hostname); + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->name, cl->hostname); cl->status.outgoing = 0; old->status.outgoing = 1; terminate_connection(cl); return 0; } } - - /* Send a challenge to verify the identity */ - - cl->allow_request = CHAL_REPLY; +cp + if((cfg = get_config_val(cl->config, config_publickey))) + { + cl->rsa_key = RSA_new(); + BN_hex2bn(&cl->rsa_key->n, cfg->data.ptr); + BN_hex2bn(&cl->rsa_key->e, "FFFF"); + } + else + { + syslog(LOG_ERR, _("No public key known for %s (%s)"), cl->name, cl->hostname); + return -1; + } cp return send_challenge(cl); } @@ -179,198 +243,348 @@ cp int send_challenge(conn_list_t *cl) { char *buffer; - int keylength; - int x; + int len, x; cp - if(cl->chal_hash) - free(cl->chal_hash); - - /* Allocate buffers for the challenge and the hash */ - - cl->chal_hash = xmalloc(SHA_DIGEST_LEN); - keylength = BN_num_bytes(cl->rsakey.n); - buffer = xmalloc(keylength*2); + len = RSA_size(cl->rsa_key); - /* Copy random data and the public key to the buffer */ - - RAND_bytes(buffer, keylength); - BN_bn2bin(cl->rsakey.n, buffer+keylength); + /* Allocate buffers for the challenge */ - /* If we don't have a blowfish key set yet, use the random data from the challenge to do so. */ - - if(!cl->status.encrypted) - { - set_metakey(cl, buffer, keylength); - } + buffer = xmalloc(len*2+1); - /* Calculate the hash from that */ + if(cl->hischallenge) + free(cl->hischallenge); + + cl->hischallenge = xmalloc(len); +cp + /* Copy random data to the buffer */ - SHA1(buffer, keylength*2, cl->chal_hash); + RAND_bytes(cl->hischallenge, len); - /* Convert the random data to a hexadecimal formatted string */ + cl->hischallenge[0] &= 0x7F; /* Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ - bin2hex(buffer,buffer,keylength); - buffer[keylength*2] = '\0'; + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->hischallenge, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Generated random challenge (unencrypted): %s"), buffer); + } - /* Send the challenge */ + /* Encrypt the random data */ + if(RSA_public_encrypt(len, cl->hischallenge, buffer, cl->rsa_key, RSA_NO_PADDING) != len) /* NO_PADDING because the message size equals the RSA key size and it is totally random */ + { + syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); + free(buffer); + return -1; + } +cp + /* Convert the encrypted random data to a hexadecimal formatted string */ + + bin2hex(buffer, buffer, len); + buffer[len*2] = '\0'; + + /* Send the challenge */ + cl->allow_request = CHAL_REPLY; x = send_request(cl, "%d %s", CHALLENGE, buffer); free(buffer); - cl->status.encrypted = 1; cp return x; } int challenge_h(conn_list_t *cl) { - char *challenge; + char *buffer; + int len; cp - if(sscanf(cl->buffer, "%*d %as", &cl->id, &challenge) != 1) + if(sscanf(cl->buffer, "%*d %as", &buffer) != 1) { - syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname); return -1; } - /* Rest is done by send_chal_reply() */ - - x = send_chal_reply(cl, challenge); - free(challenge); -cp - return x; -} - -int send_chal_reply(conn_list_t *cl, char *challenge) -{ - char *buffer; - int keylength; - char *hash; - int x; -cp - keylength = BN_num_bytes(myself->rsakey.n); + len = RSA_size(myself->rsa_key); /* Check if the length of the challenge is all right */ - if(strlen(challenge) != keylength*2) + if(strlen(buffer) != len*2) { - syslog(LOG_ERROR, _("Intruder: wrong challenge length from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname); + free(buffer); return -1; } - /* Allocate buffers for the challenge and the hash */ - - buffer = xmalloc(keylength*2); - hash = xmalloc(SHA_DIGEST_LEN*2+1); + /* Allocate buffers for the challenge */ - /* Copy the incoming random data and our public key to the buffer */ + if(!cl->mychallenge) + cl->mychallenge = xmalloc(len); - hex2bin(challenge, buffer, keylength); - BN_bn2bin(myself->rsakey.n, buffer+keylength); + /* Convert the challenge from hexadecimal back to binary */ - /* Calculate the hash from that */ - - SHA1(buffer, keylength*2, hash); + hex2bin(buffer,buffer,len); - /* If we don't have a blowfish key set yet, use the random data from the challenge to do so. */ + /* Decrypt the challenge */ - if(!cl->status.encrypted) + if(RSA_private_decrypt(len, buffer, cl->mychallenge, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */ { - set_metakey(cl, buffer, keylength); - cl->status.encrypted = 1; + syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); + free(buffer); + return -1; + } + + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->mychallenge, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Received random challenge (unencrypted): %s"), buffer); } free(buffer); + + /* Rest is done by send_chal_reply() */ +cp + return send_chal_reply(cl); +} + +int send_chal_reply(conn_list_t *cl) +{ + char hash[SHA_DIGEST_LENGTH*2+1]; +cp + if(!cl->mychallenge) + { + syslog(LOG_ERR, _("Trying to send CHAL_REPLY to %s (%s) without a valid CHALLENGE"), cl->name, cl->hostname); + return -1; + } + + /* Calculate the hash from the challenge we received */ + + SHA1(cl->mychallenge, RSA_size(myself->rsa_key), hash); /* Convert the hash to a hexadecimal formatted string */ - bin2hex(hash,hash,SHA_DIGEST_LEN); - hash[SHA_DIGEST_LEN*2] = '\0'; + bin2hex(hash,hash,SHA_DIGEST_LENGTH); + hash[SHA_DIGEST_LENGTH*2] = '\0'; /* Send the reply */ if(cl->status.outgoing) - cl->allow_resuest = ID; + cl->allow_request = ID; else - cl->allow_request = ACK; + cl->allow_request = METAKEY; - x = send_request(cl, "%d %s", CHAL_REPLY, hash); - free(hash); cp - return x; -} + return send_request(cl, "%d %s", CHAL_REPLY, hash); +} int chal_reply_h(conn_list_t *cl) { - char *hash; + char *hishash; + char myhash[SHA_DIGEST_LENGTH]; cp - if(sscanf(cl->buffer, "%*d %as", &cl->id, &hash) != 2) + if(sscanf(cl->buffer, "%*d %as", &hishash) != 1) { - syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname); + free(hishash); return -1; } /* Check if the length of the hash is all right */ - - if(strlen(hash) != SHA_DIGEST_LEN*2) + + if(strlen(hishash) != SHA_DIGEST_LENGTH*2) { - syslog(LOG_ERROR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname); + free(hishash); return -1; } - + /* Convert the hash to binary format */ - - hex2bin(hash, hash, SHA_DIGEST_LEN); - + + hex2bin(hishash, hishash, SHA_DIGEST_LENGTH); + + /* Calculate the hash from the challenge we sent */ + + SHA1(cl->hischallenge, RSA_size(cl->rsa_key), myhash); + /* Verify the incoming hash with the calculated hash */ - - if{!memcmp(hash, cl->chal_hash, SHA_DIGEST_LEN)} + + if(memcmp(hishash, myhash, SHA_DIGEST_LENGTH)) { - syslog(LOG_ERROR, _("Intruder: wrong challenge reply from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Intruder: wrong challenge reply from %s (%s)"), cl->name, cl->hostname); + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(myhash, hishash, SHA_DIGEST_LENGTH); + hishash[SHA_DIGEST_LENGTH*2] = '\0'; + syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash); + } + free(hishash); return -1; } + + free(hishash); + /* Identity has now been positively verified. If we are accepting this new connection, then send our identity, if we are making this connecting, acknowledge. */ - - free(hash); - free(cl->chal_hash); - cp if(cl->status.outgoing) + return send_metakey(cl); + else + return send_id(cl); +} + +int send_metakey(conn_list_t *cl) +{ + char *buffer; + int len, x; +cp + len = RSA_size(cl->rsa_key); + + /* Allocate buffers for the meta key */ + + buffer = xmalloc(len*2+1); + + if(!cl->cipher_outkey) + cl->cipher_outkey = xmalloc(len); + + if(!cl->cipher_outctx) + cl->cipher_outctx = xmalloc(sizeof(*cl->cipher_outctx)); +cp + /* Copy random data to the buffer */ + + RAND_bytes(cl->cipher_outkey, len); + + cl->cipher_outkey[0] &= 0x7F; /* FIXME: Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ + + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->cipher_outkey, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), buffer); + } + + /* Encrypt the random data */ + + if(RSA_public_encrypt(len, cl->cipher_outkey, buffer, cl->rsa_key, RSA_NO_PADDING) != len) /* NO_PADDING because the message size equals the RSA key size and it is totally random */ { - cl->allow_request = ACK; - return send_ack(cl); + syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname); + free(buffer); + return -1; } +cp + /* Convert the encrypted random data to a hexadecimal formatted string */ + + bin2hex(buffer, buffer, len); + buffer[len*2] = '\0'; + + /* Send the meta key */ + + if(cl->status.outgoing) + cl->allow_request = METAKEY; else + cl->allow_request = ACK; + + x = send_request(cl, "%d %s", METAKEY, buffer); + free(buffer); + + EVP_EncryptInit(cl->cipher_outctx, EVP_bf_cfb(), cl->cipher_outkey, cl->cipher_outkey + EVP_bf_cfb()->key_len); +cp + return x; +} + +int metakey_h(conn_list_t *cl) +{ + char *buffer; + int len; +cp + if(sscanf(cl->buffer, "%*d %as", &buffer) != 1) { - cl->allow_request = CHALLENGE; - return send_id(cl); + syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), cl->name, cl->hostname); + return -1; + } + + len = RSA_size(myself->rsa_key); + + /* Check if the length of the meta key is all right */ + + if(strlen(buffer) != len*2) + { + syslog(LOG_ERR, _("Intruder: wrong meta key length from %s (%s)"), cl->name, cl->hostname); + free(buffer); + return -1; } + + /* Allocate buffers for the meta key */ + + if(!cl->cipher_inkey) + cl->cipher_inkey = xmalloc(len); + + if(!cl->cipher_inctx) + cl->cipher_inctx = xmalloc(sizeof(*cl->cipher_inctx)); + + /* Convert the challenge from hexadecimal back to binary */ + + hex2bin(buffer,buffer,len); + + /* Decrypt the meta key */ + + if(RSA_private_decrypt(len, buffer, cl->cipher_inkey, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */ + { + syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname); + free(buffer); + return -1; + } + + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->cipher_inkey, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer); + } + + free(buffer); + + EVP_DecryptInit(cl->cipher_inctx, EVP_bf_cfb(), cl->cipher_inkey, cl->cipher_inkey + EVP_bf_cfb()->key_len); + +cp + if(cl->status.outgoing) + return send_ack(cl); + else + return send_metakey(cl); } int send_ack(conn_list_t *cl) { + int x; cp - return send_request(cl, "%d", ACK); + if(cl->status.outgoing) + cl->allow_request = ACK; + + setup_vpn_connection(cl); + + x = send_request(cl, "%d", ACK); + cl->status.encryptout = 1; +cp + return x; } int ack_h(conn_list_t *cl) { - conn_list_t old; + conn_list_t *old, *p; + subnet_t *s; cp /* Okay, before we active the connection, we check if there is another entry - in the connection list with the same vpn_ip. If so, it presumably is an + in the connection list with the same name. If so, it presumably is an old connection that has timed out but we don't know it yet. */ - while((old = lookup_id(cl->id))) + while((old = lookup_id(cl->name))) { - if(debug_lvl > DEBUG_CONNECTIONS) + if(debug_lvl >= DEBUG_CONNECTIONS) syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"), - cl->id, old->hostname, cl->hostname); - old->status.active = 0; + cl->name, old->hostname, cl->hostname); + terminate_connection(old); } @@ -378,44 +592,204 @@ cp cl->allow_request = ALL; cl->status.active = 1; + cl->status.decryptin = 1; + cl->nexthop = cl; + cl->cipher_pkttype = EVP_bf_cfb(); + cl->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->id, cl->hostname); + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname); - /* Exchange information about other tinc daemons */ +cp + if(!cl->status.outgoing) + send_ack(cl); - notify_others(cl, NULL, send_add_host); - notify_one(cl); + /* Send him our subnets */ + + for(s = myself->subnets; s; s = s->next) + send_add_subnet(cl, s); + + /* And send him all the hosts and their subnets we know... */ + + for(p = conn_list; p; p = p->next) + if(p != cl && p->status.active) + { + /* Notify others of this connection */ + + if(p->status.meta) + send_add_host(p, cl); - upstreamindex = 0; + /* Notify new connection of everything we know */ + send_add_host(cl, p); + + for(s = p->subnets; s; s = s->next) + send_add_subnet(cl, s); + } cp - if(cl->status.outgoing) - return 0; - else - return send_ack(cl); + return 0; } /* Address and subnet information exchange */ -int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet) +int send_add_subnet(conn_list_t *cl, subnet_t *subnet) { + int x; + char *netstr; cp - return send_request(cl, "%d %s %d %s", ADD_SUBNET, other->id, subnet->type, net2str(subnet)); + x = send_request(cl, "%d %s %s", ADD_SUBNET, + subnet->owner->name, netstr = net2str(subnet)); + free(netstr); +cp + return x; } int add_subnet_h(conn_list_t *cl) { + char *subnetstr; + char *name; + conn_list_t *owner, *p; + subnet_t *subnet; +cp + if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 2) + { + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if owner name is a valid */ + + if(check_id(name)) + { + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if subnet string is valid */ + + if(!(subnet = str2net(subnetstr))) + { + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + free(subnetstr); + + /* Check if somebody tries to add a subnet of ourself */ + + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got ADD_SUBNET from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); + sighup = 1; + return 0; + } + + /* Check if the owner of the new subnet is in the connection list */ + + if(!(owner = lookup_id(name))) + { + syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); + return -1; + } + + /* If everything is correct, add the subnet to the list of the owner */ + + subnet_add(owner, subnet); + + /* Tell the rest */ + + for(p = conn_list; p; p = p->next) + if(p->status.meta && p->status.active && p!= cl) + send_add_subnet(p, subnet); +cp + return 0; } -int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet) +int send_del_subnet(conn_list_t *cl, subnet_t *subnet) { + int x; + char *netstr; +cp + netstr = net2str(subnet); + x = send_request(cl, "%d %s %s", DEL_SUBNET, subnet->owner->name, netstr); + free(netstr); cp - return send_request(cl, "%d %s %d %s", DEL_SUBNET, other->id, subnet->type, net2str(subnet)); + return x; } int del_subnet_h(conn_list_t *cl) { + char *subnetstr; + char *name; + conn_list_t *owner, *p; + subnet_t *subnet; +cp + if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if owner name is a valid */ + + if(check_id(name)) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if subnet string is valid */ + + if(!(subnet = str2net(subnetstr))) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + free(subnetstr); + + /* Check if somebody tries to add a subnet of ourself */ + + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); + sighup = 1; + return 0; + } + + /* Check if the owner of the new subnet is in the connection list */ + + if(!(owner = lookup_id(name))) + { + syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); + return -1; + } + + /* If everything is correct, delete the subnet from the list of the owner */ + + subnet_del(subnet); + + /* Tell the rest */ + + for(p = conn_list; p; p = p->next) + if(p->status.meta && p->status.active && p!= cl) + send_del_subnet(p, subnet); +cp + return 0; } /* New and closed connections notification */ @@ -423,83 +797,91 @@ int del_subnet_h(conn_list_t *cl) int send_add_host(conn_list_t *cl, conn_list_t *other) { cp - return send_request(cl, "%d %s %lx:%d %s", ADD_HOST, other->id, other->address, other->port, opt2str(other->options)); + return send_request(cl, "%d %s %lx:%d %lx", ADD_HOST, + other->name, other->address, other->port, other->options); } int add_host_h(conn_list_t *cl) { - char *options; conn_list_t *old, *new; + conn_list_t *p; + cp new = new_conn_list(); - if(sscanf(cl->buffer, "%*d %as %lx:%d %as", &new->id, &new->address, &new->port, &options) != 4) + if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &new->name, &new->address, &new->port, &new->options) != 4) { - syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->name, cl->hostname); return -1; - } - - /* Check if option string is valid */ - - if((new->options = str2opt(options) == -1) - { - syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid option string"), cl->hostname); - return -1; } /* Check if identity is a valid name */ - - if(!check_id(new->id)) + + if(check_id(new->name)) { - syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + free_conn_list(new); return -1; } - + /* Check if somebody tries to add ourself */ - - if(!strcmp(new->id, myself->id)) + + if(!strcmp(new->name, myself->name)) { - syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); sighup = 1; + free_conn_list(new); return 0; } - + /* Fill in more of the new conn_list structure */ new->hostname = hostlookup(htonl(new->address)); - + /* Check if the new host already exists in the connnection list */ - if((old = lookup_id(id)) + if((old = lookup_id(new->name))) { if((new->address == old->address) && (new->port == old->port)) { - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), old->id, old->hostname, new->id, new->hostname); - return 0; + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), + old->name, old->hostname, new->name, new->hostname); + free_conn_list(new); + return 0; } else { - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), old->id, old->hostname); - old->status.active = 0; + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Removing old entry for %s (%s) in favour of new connection"), + old->name, old->hostname); + terminate_connection(old); } } + /* Hook it up into the conn_list */ + + conn_list_add(new); + + /* Tell the rest about the new host */ + + for(p = conn_list; p; p = p->next) + if(p->status.meta && p->status.active && p!=cl) + send_add_host(p, new); + /* Fill in rest of conn_list structure */ new->nexthop = cl; new->status.active = 1; - - /* Hook it up into the conn_list */ - - conn_list_add(conn_list, new); + new->cipher_pkttype = EVP_bf_cfb(); + new->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; - /* Tell the rest about the new host */ - - notify_others(new, cl, send_add_host); - + /* Okay this is a bit ugly... it would be better to setup UDP sockets dynamically, or + * perhaps just one UDP socket... but then again, this has benefits too... + */ + + setup_vpn_connection(new); cp return 0; } @@ -507,52 +889,73 @@ cp int send_del_host(conn_list_t *cl, conn_list_t *other) { cp - return send_request(cl, "%d %s %lx:%d", DEL_HOST, other->id, other->address, other->port); + return send_request(cl, "%d %s %lx:%d %lx", DEL_HOST, + other->name, other->address, other->port, other->options); } int del_host_h(conn_list_t *cl) { - char *id; + char *name; ip_t address; port_t port; - conn_list_t *old; + long int options; + conn_list_t *old, *p; cp - if(sscanf(cl->buffer, "%*d %as %lx:%d", &id, &address, &port) != 3) + if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &name, &address, &port, &options) != 4) { - syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), cl->id, cl->hostname); - return -1; - } + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), + cl->name, cl->hostname); + return -1; + } + + /* Check if identity is a valid name */ + + if(check_id(name)) + { + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); + return -1; + } /* Check if somebody tries to delete ourself */ - - if(!strcmp(id, myself->id)) + + if(!strcmp(name, myself->name)) { - syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); sighup = 1; return 0; } /* Check if the new host already exists in the connnection list */ - if((old = lookup_id(id)) + if(!(old = lookup_id(name))) { - if((address == old->address) && (port == old->port)) - { - notify_others(old, cl, send_del_host); - - fw->status.termreq = 1; - fw->status.active = 0; - - terminate_connection(fw); -cp - return 0; - } + syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) for %s which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); + return -1; } - - if(debug_lvl > DEBUG_CONNECTIONS) + + /* Check if the rest matches */ + + if(address!=old->address || port!=old->port || options!=old->options || cl!=old->nexthop) { - syslog(LOG_NOTICE, _("Got DEL_HOST for %s from %s (%s) which is not in our connection list"), id, cl->id, cl->hostname); + syslog(LOG_WARNING, _("Got DEL_HOST from %s (%s) for %s which doesn't match"), cl->name, cl->hostname, old->name); + return 0; } + + /* Ok, since EVERYTHING seems to check out all right, delete it */ + + old->status.active = 0; + terminate_connection(old); + + /* Tell the rest about the new host */ + + for(p = conn_list; p; p = p->next) + if(p->status.meta && p->status.active && p!=cl) + send_del_host(p, old); cp return 0; } @@ -575,13 +978,15 @@ int status_h(conn_list_t *cl) cp if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2) { - syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), + cl->name, cl->hostname); return -1; } - if(debug_lvl > DEBUG_STATUS) + if(debug_lvl >= DEBUG_STATUS) { - syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), cl->id, cl->hostname, status_text[statusno], statusstring); + syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), + cl->name, cl->hostname, status_text[statusno], statusstring); } cp @@ -592,8 +997,8 @@ cp int send_error(conn_list_t *cl, int errno, char *errstring) { cp - if(!errorstring) - errorstring = error_text[errno]; + if(!errstring) + errstring = strerror(errno); return send_request(cl, "%d %d %s", ERROR, errno, errstring); } @@ -604,17 +1009,18 @@ int error_h(conn_list_t *cl) cp if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2) { - syslog(LOG_ERR, _("Got bad error from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad ERROR from %s (%s)"), + cl->name, cl->hostname); return -1; } - if(debug_lvl > DEBUG_error) + if(debug_lvl >= DEBUG_ERROR) { - syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), cl->id, cl->hostname, error_text[errno], errorstring); + syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), + cl->name, cl->hostname, strerror(errno), errorstring); } free(errorstring); - cl->status.termreq = 1; terminate_connection(cl); cp return 0; @@ -629,7 +1035,6 @@ cp int termreq_h(conn_list_t *cl) { cp - cl->status.termreq = 1; terminate_connection(cl); cp return 0; @@ -639,7 +1044,9 @@ cp int send_ping(conn_list_t *cl) { +cp cl->status.pinged = 1; + cl->last_ping_time = time(NULL); cp return send_request(cl, "%d", PING); } @@ -659,7 +1066,7 @@ cp int pong_h(conn_list_t *cl) { cp - cl->status.got_pong = 1; + cl->status.pinged = 0; cp return 0; } @@ -673,7 +1080,8 @@ cp for(p = conn_list; p != NULL; p = p->next) { if(p!=cl && p->status.meta && p->status.active) - send_request(p, "%d %s", KEY_CHANGED, from->id); + send_request(p, "%d %s", KEY_CHANGED, + from->name); } cp return 0; @@ -686,66 +1094,83 @@ int key_changed_h(conn_list_t *cl) cp if(sscanf(cl->buffer, "%*d %as", &from_id) != 1) { - syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), cl->id, cl->hostname); - return -1; - } + syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), + cl->name, cl->hostname); + return -1; + } if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, _("Got KEY_CHANGED from %s (%s) origin %s which does not exist in our connection list"), cl->id, cl->hostname, from_id); + syslog(LOG_ERR, _("Got KEY_CHANGED from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); free(from_id); return -1; } free(from_id); - + from->status.validkey = 0; from->status.waitingforkey = 0; - + send_key_changed(from, cl); cp return 0; } - + int send_req_key(conn_list_t *from, conn_list_t *to) { cp - return send_request(to->nexthop, "%d %s %s", REQ_KEY, from->id, to->id); + return send_request(to->nexthop, "%d %s %s", REQ_KEY, + from->name, to->name); } int req_key_h(conn_list_t *cl) { char *from_id, *to_id; conn_list_t *from, *to; + char pktkey[129]; cp if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2) { - syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), + cl->name, cl->hostname); return -1; - } + } if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) origin %s which does not exist in our connection list"), cl->id, cl->hostname, from_id); + syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); free(from_id); free(to_id); return -1; } /* Check if this key request is for us */ - if(!strcmp(id, myself->strcmp)) + if(!strcmp(to_id, myself->name)) { - send_ans_key(myself, from, myself->datakey); + bin2hex(myself->cipher_pktkey, pktkey, myself->cipher_pktkeylength); + pktkey[myself->cipher_pktkeylength*2] = '\0'; + send_ans_key(myself, from, pktkey); } else { if(!(to = lookup_id(to_id))) { - syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) destination %s which does not exist in our connection list"), cl->id, cl->hostname, to_id); + syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) destination %s which does not exist in our connection list"), + cl->name, cl->hostname, to_id); free(from_id); free(to_id); return -1; } - send_req_key(from, to); + + if(to->status.validkey) /* Proxy keys */ + { + bin2hex(to->cipher_pktkey, pktkey, to->cipher_pktkeylength); + pktkey[to->cipher_pktkeylength*2] = '\0'; + send_ans_key(to, from, pktkey); + } + else + send_req_key(from, to); } free(from_id); free(to_id); @@ -753,105 +1178,82 @@ cp return 0; } -int send_ans_key(conn_list_t *from, conn_list_t *to, char *datakey) +int send_ans_key(conn_list_t *from, conn_list_t *to, char *pktkey) { cp - return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, from->id, to->id, datakey); + return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, + from->name, to->name, pktkey); } int ans_key_h(conn_list_t *cl) { - char *from_id, *to_id, *datakey; + char *from_id, *to_id, *pktkey; int keylength; conn_list_t *from, *to; cp - if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &datakey) != 3) + if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &pktkey) != 3) { - syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), cl->id, cl->hostname); + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), + cl->name, cl->hostname); return -1; - } + } if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) origin %s which does not exist in our connection list"), cl->id, cl->hostname, from_id); - free(from_id); free(to_id); free(datakey); + syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); + free(from_id); free(to_id); free(pktkey); return -1; } - /* Check if this key request is for us */ + /* Check correctness of packet key */ + + keylength = strlen(pktkey); - if(!strcmp(id, myself->strcmp)) + if(keylength != from->cipher_pktkeylength*2) { - /* It is for us, convert it to binary and set the key with it. */ - - keylength = strlen(datakey); - - if((keylength%2) || (keylength <= 0)) - { - syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"), cl->id, cl->hostname, from->id); - free(from_id); free(to_id); free(datakey); - return -1; - } - keylength /= 2; - hex2bin(datakey, datakey, keylength); - BF_set_key(cl->datakey, keylength, datakey); + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key length"), + cl->name, cl->hostname, from->name); + free(from_id); free(to_id); free(pktkey); + return -1; } - else + + /* Forward it if necessary */ + + if(strcmp(to_id, myself->name)) { if(!(to = lookup_id(to_id))) { - syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"), cl->id, cl->hostname, to_id); - free(from_id); free(to_id); free(datakey); + syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"), + cl->name, cl->hostname, to_id); + free(from_id); free(to_id); return -1; } - send_ans_key(from, to, datakey); + send_ans_key(from, to, pktkey); } - free(from_id); free(to_id); free(datakey); -cp - return 0; -} - -/* Old routines */ - -/* - Notify all my direct connections of a new host - that was added to the vpn, with the exception - of the source of the announcement. -*/ + /* Update our copy of the origin's packet key */ -int notify_others(conn_list_t *new, conn_list_t *source, - int (*function)(conn_list_t*, conn_list_t*)) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p != source && p->status.meta && p->status.active) - function(p, new); -cp - return 0; -} + if(from->cipher_pktkey) + free(from->cipher_pktkey); -/* - Notify one connection of everything - I have connected -*/ + keylength /= 2; + hex2bin(pktkey, pktkey, keylength); + pktkey[keylength] = '\0'; + from->cipher_pktkey = pktkey; -int notify_one(conn_list_t *new) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p->status.active) - send_add_host(new, p); + from->status.validkey = 1; + from->status.waitingforkey = 0; + + free(from_id); free(to_id); cp return 0; } -/* "Complete overhaul". */ +/* Jumptable for the request handlers */ int (*request_handlers[])(conn_list_t*) = { - id_h, challenge_h, chal_reply_h, ack_h, + id_h, challenge_h, chal_reply_h, metakey_h, ack_h, status_h, error_h, termreq_h, ping_h, pong_h, add_host_h, del_host_h, @@ -859,11 +1261,25 @@ int (*request_handlers[])(conn_list_t*) = { key_changed_h, req_key_h, ans_key_h, }; +/* Request names */ + char (*request_name[]) = { - "ID", "CHALLENGE", "CHAL_REPLY", "ACK", + "ID", "CHALLENGE", "CHAL_REPLY", "METAKEY", "ACK", "STATUS", "ERROR", "TERMREQ", "PING", "PONG", "ADD_HOST", "DEL_HOST", "ADD_SUBNET", "DEL_SUBNET", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", }; + +/* Status strings */ + +char (*status_text[]) = { + "Warning", +}; + +/* Error strings */ + +char (*error_text[]) = { + "Error", +};